387: Homotypic Dengue Reinfections and Long-Term Antibody Decay

Andrade J et al., PNAS - Analysis of three long-term cohorts in the Philippines and Thailand shows antibody titers wane over years and that homotypic dengue reinfections are common and required to explain population-level age–titer patterns. Key terms: dengue, homotypic reinfection, antibody kinetics, cohort study, mathematical modelling. Study Highlights:The authors analyzed serology and PCR surveillance from three cohorts (N = 4,268) in Cebu, Philippines and Kamphaeng Phet, Thailand with up to 11 years of follow-up. Individual titers after infection show biexponential decay: a rapid short-term fall (~2 months half-life) followed by a slow long-term decline (half-life ~4–8 years) that slows with age. Catalytic models that allow waning homotypic immunity and reinfection are required to reproduce observed age-specific infection rates and mean titers, estimating many individuals experience multiple homotypic reinfections across life in high-endemic settings. Conclusion:Waning long-term antibody titers and consequent homotypic reinfections are a key feature of endemic dengue transmission; vaccines that mimic natural infection may not provide lifelong protection and control strategies should account for repeated immune-stimulating events across ages. Music:Enjoy the music based on this article at the end of the episode. Article title:Long-term antibody dynamics challenge the paradigm of lifelong homotypic immunity to dengue virus First author:Andrade J Journal:PNAS DOI:10.1073/pnas.2606206123 Reference:Andrade J, Mitard de Girardie A, Huang AT, et al. Long-term antibody dynamics challenge the paradigm of lifelong homotypic immunity to dengue virus. PNAS. 2026;123(22):e2606206123. doi:10.1073/pnas.2606206123 License:This episode is based on an open-access article published under the Creative Commons Attribution 4.0 International License (CC BY 4.0) – https://creativecommons.org/licenses/by/4.0/ Support:Base by Base – Stripe donations: https://donate.stripe.com/7sY4gz71B2sN3RWac5gEg00 Official website https://basebybase.com On PaperCast Base by Base you'll discover the latest in genomics, functional genomics, structural genomics, and proteomics. Episode link: https://basebybase.com/episodes/homotypic-reinfection-dengue QC:This episode was checked against the original article PDF and publication metadata for the episode release published on 2026-06-09. QC Scope:- article metadata and core scientific claims from the narration- excludes analogies, intro/outro, and music- transcript coverage: Audited the transcript's coverage of dengue immunity dynamics, cohort data, subclinical infection prevalence, modeling of homotypic reinfection, age-related patterns, and public health/vaccine implications. Also checked limitations and caveats discussed in the article are echoed in the transcript.- transcript topics: DENV serotypes and lifelong immunity paradigm; Cohort data and serology methods (PRNT, HI); Subclinical infections and catalytic modeling; Two-phase antibody decay (short-term and long-term); Homotypic reinfection and population immunity; Age-specific infection risk and force of infection QC Summary:- factual score: 10/10- metadata score: 10/10- supported core claims: 6- claims flagged for review: 0- metadata checks passed: 4- metadata issues found: 0 Metadata Audited:- article_doi- article_title- article_journal- license Factual Items Audited:- Three cohorts totaling N = 4,268 participants across Cebu, Philippines and Kamphaeng Phet, Thailand- Approximately 94% of infections are subclinical- Antibody titers show biexponential decay after infection: a rapid short-term drop followed by a slower long-term decline- Short-term h...